Hydrochloric Acid → HCID 178424441, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 114.76 g (purity: 95.9%; 743 mmol) of 2-cyclopropyl-6-methylphenol and 70.0 g of t-butanol was charged into an autoclave, and 72.8 g (purity: 98.0%; 743 mmol) of sodium t-butoxide was added to the mixture over one hour, and then stirred at 70° C. for 30 minutes. The resultant solution was cooled to 40° C., and then 25.0 g (purity: 98%; 148.6 mmol) of 4-hydroxy-3,6-dichloropyridazine was added to the solution. Then, the resultant mixture was heated from 40° C. to 140° C. to effect a reaction for 24 hours. After completion of the reaction, the reaction mixture was cooled to room temperature, and 750 g of pure water and 574 g of toluene were added to the cooled mixture and stirred for 30 minutes. Then, 41.7 g (400 mmol) of a 35% aqueous hydrochloric acid solution was added dropwise to the mixture, and an organic phase containing 2-cyclopropyl-6-methylphenol added in an excess amount was separated. 287 g of toluene was added to the resultant aqueous phase and stirred at room temperature for 30 minutes, and then an organic phase was separated. Then, the resultant aqueous phase containing a sodium salt of 6-chloro-3-(2-cyclopropyl-6-methylphenoxy)-4-pyridazinol was added dropwise to 20.5 g (196 mmol) of a 35% aqueous hydrochloric acid solution at 0° C. to deposit solids, followed by filtration. The resultant solids were washed with pure water and dried under a reduced pressure, and dissolved in an organic solvent and quantitatively determined by an HPLC internal standard analysis method, which showed that 41.2 g of 6-chloro-3-(2-cyclopropyl-6-methylphenoxy)-4-pyridazinol (purity: 85.4%; yield: 87.0%) and 29 mg of 3-chloro-6-(2-cyclopropyl-6-methylphenoxy)-4-pyridazinol (yield: 1.4%) were obtained.

Provenance & Evidence